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• Aim: How do we graph basic sin and cos curves? (y=sinx and y=cosx)

• Before we start with the video, copy these questions into your notebooks. You will need these notes to help you graph any trig function.

1. What are the important points of the unit circle to use?
2. Where, in radians, are the points located?
3. What is a period?
4. What is an amplitude?
5. How do you figure out an amplitude by looking at a graph?
6. How do you figure out an amplitude from looking at an equation?

Video

• Now, it is your turn to graph y=sinx in your notebook. Be sure to write the angles you need for the period and write down what the amplitude.

• Try these problems...

1. Sketch the graph of y=sinx in the interval 0<x<4pi

a. In the interval 0<x<4pi, for what values of x is the graph y=sinx increasing?
b. In the interval 0<x<4pi, for what values of x is the graph y=sinx decreasing?
c. How many cycles (periods) of the graph y=cosx are in the interval 0<x<4pi?

2. Is the basic sin function one-to-one? Justify your answer

3. Is the basic cosine function one-to-one? Justify your answer?

• Journal entry: Explain the statement: "The sunrise at a particular location for a full year can be represented by a sine curve."

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